Log sawing system

ABSTRACT

A log sawing system for transversely cutting logs of wound paper (such as toilet tissue or toweling) which includes a bucket conveyor for receiving the elongated logs and dumping them into at least four lanes wherein the logs are advanced toward an orbital saw in sequential fashion.

United States Patent Nystrand Sept. 16, 1975 LOG SAWING SYSTEM 3,292,470 12/1966 Nystrand et al. 83/174 [75] Inventor: Ernst D. Nystrand, Green Bay, Wis. [73] Assignee: Paper Converting Machine Primary Examiner D?nald Schran Company Green Bay Wis Attorney, Agent, or F zrm- Dawson, Tllton, Fallon &

' Lungmus [22] Filed: Sept. 6, 1974 [2]] App]. No.: 500,293 [57] ABSTRACT A log sawing system for transversely cutting logs of 152 U.S. c1 83/155; 83/174 wound paper (such as toilet tissue or toweling) which 51 11 c1 B26d 3/16; B..6d 7/12 includes a bucket Conveyor for receiving the 810m [58] Fleld of Search 83/155, 174 gated logs and dumping them into at least four lanes wherein the logs are advanced toward an orbital saw [56] References Cited in sequential fashion.

UNITED STATES PATENTS 3,213,731 10/1965 Renard 83/174 1 Claim, 10 Drawing Figures ATENTED SEP 1 6 ms sum 3 0f 4 8 8 mm mm LOG SAWING SYSTEM BACKGROUND AND SUMMARY OF INVENTION come important to avoid speed limitations in the converting equipment following the rewinder, i.e., the log saw. Through the practice of the invention a system is provided that not only eliminates a bottleneck in the converting of webs but is compact, yet rugged and simple. The system includes a bucket conveyor for delivering the logs to at least four parallel lanes wherein the logs are advanced toward an orbital saw. The advancement of thelogs is in a sequentially indexed fashion so that as the log in one lane has been severed, it is advanced while the saw is performing its function on an adjacent log. Thereafter, the severed log portions are delivered into a speed-up conveyor which advantageously removes the trim portions of the log.

Other advantages and objectives of the invention may be seen in the details of constructions set forth in the ensuing specification.

DETAILED DESCRIPTION The invention is described in conjunction with an il lustrative embodiment in the accompanying drawing, in which FIG. 1 is a perspective view of the inventive system as would be seen from the entering end, i.e., along the sight line l-l applied to FIG. 2;

FIG. 2 is a diagram of certain of the major elements of the system seen in FIG. 1;

FIG. 3 is a perspective view of the system as would be seen from the discharge end, i.e., along the sight line 3-3 applied to FIG. 2;

FIG. 4 is a top plan view of the log lanes and associated advancing conveyor equipment, partially broken away and expanded in portions to more conveniently illustrate the construction;

FIG. 5 is a side elevational view of the apparatus of FIG. 4, also partially broken away for convenience of illustration;

FIG. 6 is a transverse view of the four lanes illustrated in FIG. 4 such as would be seen along the sight line 66 applied to FIG. 4;

FIG. 7 is a view similar to FIG. 6 but somewhat downstream thereof showing the lane-collar arrangement employed to restrict movement of log portions within the lanes;

FIG. 8 is a side elevational view of the discharge end of the apparatus and corresponds to the discharge end showing in FIG. 4;

FIG. 9 is a fragmentary perspective view of the entering portions of the log saw lanes and corresponds to that which would be seen along the sight line 99 of FIG. 2; and

FIG. 10 is another fragmentary perspective view such as would be seen along the sight line I0l0 of FIG. 2.

In the illustration given and with reference to the first drawing sheet, the numeral designates generally a saw infeed conveyor. As illustrated in FIG. 2, this receives the output of a rewinder and may take the logs directly from the rewinder or after they have been processed through a tail seal unit. Pusher means 21 are supported on the frame 22 of the conveyor 20 to intermittently move or push logs from the conveyor 20 onto a roll down table generally designated 23. The roll down table 23 is essentially an inclined plane and may be equipped with a sensing device 24 (see FIG. 2) which senses the presence of a sufficient accumulation of logs so as to prevent the further operation of the pusher 21.

Logs (such as those designated L in FIG. 1) are sequentially transferred to a log transfer unit generally designated 25 and which is made up of a plurality of bucket conveyors 26 (see FIG. 10). The bucket conveyors are supported between spaced apart endless chains so as to move in a loop. In one part of the loop the buckets 26 receive a log and thereafter move along in an essentially horizontal path to dump the logs into the lanes generally designated 27 (see FIG. 2) for ultimate transfer to the log saw generally designated 28. In the lanes 27, the logs are again advanced along a generally horizontal path, but one is at right angles to the path of travel of logs in the transfer unit 25.

BUCKET CONVEYOR As can be best seen in FIG. 10, the log transfer unit 25 includes a frame 29. The frame 29 provides a mounting for a pair of endless chains which support the bucket conveyors therebetween. As a bucket reaches the position 26a (see FIG. 10) it is in a position to receive the log L (see the lower left hand portion of FIG. 10). This is achieved through a rotating feed element 30 which is essentially double sector shaped". In other words, the member 30 has a pair of opposed reliefs therein which serve the function of a cradle. Thus, the lowermost log L is removed from the roll down table 23 and delivered to a bucket coming into the position 26a. This will normally be the case unless a log is already within the particular bucket approaching the position 26a as might be the case when certain of the lanes 27 are inoperative, as where there is a shut down of a wrapping machine (not shown) but normally provided at the output. of the lanes 27. In such a case, a log in a particular bucket will continue around the loop for the length of time necessary to re-energize the wrapper. The presence of a log within a bucket 26 is sensed by a switch 31 (see FIG. 1) which has a finger extending into the path of a bucket and which normally is not triggered by virtue of passing through a slot 32 in each bucket 26. However, when the switch 31 is energized (as by the presence of a log within a bucket passing thereby) it operates to energize a pair of hold down cylinders 33 (see FIG. 1) which restrict gravity movement of a log into the position L and thus prevent the log from being fed into the bucket containing the logs.

As each log-filled bucket 26 moves to the right (in FIG. 10) a lug 34 (see the central portion of FIG. 10) engages a cam (not shown) to trip or rotate the bucket and thereby dump the log into a predetermined lane or trough.

Reference to FIG. 9 reveals four lanes or troughs as at 35, 36, 37 and 38. By spacing the cams or tripping elements, the buckets can be dumped in sequence so as to fill one lane after the other, i.e., 35, 36, 37 and finally 38. The generally horizontal path of the bucket conveyor can be appreciated from a consideration of FIG. 9 wherein a portion of the frame 29 (opposite to that seen in FIG. is equipped with bearings as at 39 for supporting the chain sprockets above the various lanes 3538. In FIG. 10 in the upper right hand portion a cylinder and piston rod 40 can be seen which is employed to pivot the cams or tripping elements out of position when a signal is given that a particular lane is not in condition to receive a log.

Thus, the log transfer unit receives logs sequentially from the log roll down table through the operation of the feeder element (see FIG. 10). Each bucket 26 will be filled in turn except when it already has a log therein by virtue of one of the lanes 27 being inoperative. The presence of such a log is sensed by the switch 31 (see FIG. 1) having a sensing element aligned with a slot 32, which, when tripped, actuates the air cylinders 33 to hold logs back on the roll down table. Also, when a given lane 35-38, as the case may be, is inoperative, the cylinder and piston unit associated therewith (see FIG. 10) will move the trip mechanism (not shown) out of dumping position relative to the lug 34 so that the log in that particular bucket will continue around the loop until the particular lane in question is reactivated.

SAW FEEDING LANES The four lanes illustrated and designated by the nu merals 35-38 can be seen as far as their upstream ends are concerned in FIG. 9 and as far as the downstream ends are concerned at the extreme left hand portion of FIG. 3. Logs introduced into the lanes 35-38 are pushed toward the log saw 28 by means of pushers 41 (see the central lower portion of FIG. 9). Each lane is defined in its upstream portion by a trough (see FIG. 9) which is slotted at the bottom thereof to permit the movement in the trough of the various pushers 41. For this purpose, each lane 3538 has associated therewith an endless chain as at 42, 43, 44 and respectively (still referring to FIG. 9). The chain 42 associated with the lane 35 is entrained on a sprocket 46 (see FIG. 9 and also compare the right hand portions of FIGS. 4 and 5). The chains 43 and 44 are entrained at their upstream ends on sprockets 47 and 48, respectively, while the chain 45 is entrained about the sprocket 49. It will be noted that the sprockets 47 and 48 and therefore the chains 43 and 44 are horizontally aligned. The arrangement of the various lanes can be readily appreciated from a consideration of FIG. 6 where it will be noted that the lanes 35 and 36 are on one side of what could be considered nadir of the saw orbit while the other pair of lanes 37 and 38 are on the other side. Further, the outermost lane of each pair as at 35 and 38, is higher than the two central lanes 36 and 37. In the normal operation of the leg saw 28, a log in the lane 35 is first engaged and as the saw swings downwardly and to the left (as viewed in FIG. 6) it next encounters a log in the lane 36. Through the drive arrangement to the various chains 4245, a log is indexed as soon as the saw passes through it. In other words, as soon as the saw passes through a log in the lane 35, the log in that lane is advanced and before the saw has passed through logs in the remaining lanes 36-38. Normally a log may be upwards of eight feet in length and will be advanced, i.e., indexed each orbit a distance of the order of 4 /2 inches (for US. sized toilet tissue).

For the purpose of driving the pusher chains, and for powering the orbital saw, a motor 50 (see FIGS. 35) is provided. The motor 51 is coupled by means ofa cog belt 51 to a right angled gear reducer 52 which drives a line shaft 53.

The line shaft 53, as can be best seen in FIG. 4, serves to deliver rotational power to three drive units generally designated 54, 55 and 56. The unit 54 is employed to deliver rotational power through a shaft 57 (see FIG. 4) to a sprocket 58 which is at the downstream end of the chain 45. In like fashion, the unit 55 delivers rotational power to both of the chains 43 and 44 by means of sprockets 59 and 60 which are mounted on a cross shaft 61. The chain 42 is similarly powered through the sprocket 62 fixed to the shaft 63 associated with the unit 56.

Each of the units 54-56 includes a clutch and gear unit such as is represented at 64 relative to the unit 54, the gear deriving rotational power from the line shaft 53 and delivering the same to a cam indexing unit as at 65. The output of the cam indexing unit 65 is delivered by a gear train 66 to the cross shaft 57 as in the instance of the lane 38 with which the chain 45 is associated. The other drive units 55 and 56 are similarly arranged with the exception that the middle unit 55 powers both the chains 43 and 44 associated with the lanes 36 and 37. Thus. provision is made for first advancing logs within the lane 35 (under the influence of the pushers 41 associated with the chain 42) and thereafter in the lanes 36 and 37 simultaneously and lastly in the lane 38.

It will be appreciated that the orbital saw unit generally designated 28 also derives rotational power from the line shaft 53 as by the gear train 67 (see FIG. 5). As described in US. Pat. No. 3,292,470, the log saw 28 is advantageously equipped also with a cam indexer for stopping the orbital motion of the saw once each orbit for sharpening the same. By suitable adjustment of the various cam indexing units (as at 65 relative to the drive unit 54) the chain associated with each cam indexing unit can be advanced (or indexed) as soon as the saw blade has cleared the particular lane. This then achieves a fast and efficient operation but with equipment that is compact and rugged.

Downstream of each driven sprocket, the slot in each lane is enlarged as at 68 relative to the lane 38 (see the upper central portion of FIG. 4). This permits the pushers to pass downwardly through the lane or trough in moving toward the upstream end of the trough. Brushes as at 69 are mounted along the sides of the enlargement 68 so as to permit the pushers 41 to pass therethrough yet provide support for the now severed log rolls and prevent hang up or restriction of the same.

FIG. 6 shows the construction of collar means as at 70 for confining logs upstream of the log saw 28. The collar means 70 include arcuate elements 71 for each of lanes 35-38 which are pivotally supported as at 72 on a portion of the machine frame 73. A second pivotal connection is provided at 74 coupling the collar element 71 to a slotted link 75. By adjusting the set screw 76 within the slot 77, the position of the arcuate collar elements 71 can be adjusted to accommodate different diameter logs.

In FIG. 7 additional collar elements are seen which are advantageously provided downstream of the log saw 28 and which include pivotal arcuate elements 78 also positionably fixed relative to the frame 73 and with a confining bracket arrangement generally designated 79 also supported on the frame 73.

At the extreme downstream end of the lanes 35-38, a speed-up conveyor as at 80 is provided for each of the lanes, i.e., the conveyor 80 (more precisely, an endless belt system) operates in conjunction with the lane 35 while the belt systems 81, 82 and 83 operate with lanes 36-38, respectively. it will be seen that the belts 80-83 are somewhat offset from the discharge belts 84-87 associated respectively with the lanes 35-38. Additionally, the belt systems 80-83 are operated at a somewhat faster speed than the belt systems 84-87 and thereby assist in twisting the severed log rolls (and trim portions) as they issue from the lanes 35-38. Further, as can be seen clearly in FIG. 8 the belt systems 80-83 (as exemplified by the belt system 80) are arranged with the top run essentially horizontal while the top run of the discharge belt systems 84-87 (as exemplified by the belt system 84) are at a more substantial angle so that the belts in each system 80-83 and 84-87 are arranged at an angle relative to each other which further assists in jogging the thin trim rolls which are developed by the log saw. It will be appreciated that the log is generally longer than an exact integral number of rolls to be cut therefrom, thereby producing cookies" or thin rolls (of the order of up to an inch or so) which must be disposed of, These conveniently fall between the belts and the associated guide rails as at 88 for the belt system 80 and 89 for the belt system 84.

1 claim:

1. A log transport and cutting mechanism comprising a frame,

a bucket conveyor on said frame arranged and constructed to travel in a loop, each bucket being relatively elongated and adapted to receive a log in one part of said loop and dump said log in another part of said loop whereby a log in travelling from said one loop part to said another loop part travels through a first path,

means adjacent said loop one part for feeding logs to said conveyor for each bucket, sensing means in said frame actuatable by a log in a bucket approaching said loop one part to prevent a log being fed to said conveyor for the last mentioned bucket, pusher system on said frame for advancing logs in a second path generally perpendicular to said first path, said system including at least four parallel guide lanes for the receipt of logs dumped thereinto from buckets travelling in said first path, each lane having an endless chain mounted therebelow and equipped with a plurality of pushers adapted to project into the associated lane for axially advancing a log, a rotating disk saw orbitally mounted on said frame to pass transversely and sequentially through logs in said lane, said lanes being arranged with a pair on each side of the nadir of said orbit with the outer of each pair being higher than the inner, and with the inner of each pair being horizontally aligned, collar means in each lane for confining a log therein just prior to engagement with said saw,

drive means for said saw and chains comprising a motor-powered line shaft mounted on said frame, a cam indexing unit for each of said saw and four chains coupled to said line shaft and deriving rotational power therefrom, said chain cam indexing units being arranged and constructed to index first that chain associated with the outer lane log first engaged by said saw during an orbit, next the two chains in the inner lanes of each pair and thereafter the chain associated with the outer lane, and

means operably associated with each lane for increasing the speed of the severed log portion to assist in removal of log trim. 

1. A log transport and cutting mechanism comprising a frame, a bucket conveyor on said frame arranged and constructed to travel in a loop, each bucket being relatively elongated and adapted to receive a log in one part of said loop and dump said log in another part of said loop whereby a log in travelling from said one loop part to said another loop part travels through a first path, means adjacent said loop one part for feeding logs to said conveyor for each bucket, sensing means in said frame actuatable by a log in a bucket approaching said loop one part to prevent a log being fed to said conveyor for the last mentioned bucket, a pusher system on said frame for advancing logs in a second path generally perpendicular to said first path, said system including at least four parallel guide lanes for the receipt of logs dumped thereinto from buckets travelling in said first path, each lane having an endless chain mounted therebelow and equipped with a plurality of pushers adapted to project into the associated lane for axially advancing a log, a rotating disk saw orbitally mounted on said frame to pass transversely and sequentially through logs in said lane, said lanes being arranged with a pair on each side of the nadir of said orbit with the outer of each pair being higher than the inner, and with the inner of each pair being horizontally aligned, collar means in each lane for confining a log therein just prior to engagement with said saw, drive means for said saw and chains comprising a motor-powered line shaft mounted on said frame, a cam indexing unit for each of said saw and four chains coupled to said line shaft and deriving rotational power therefrom, said chain cam indexing units being arranged and constructed to index first that chain associated with the outer lane log first engaged by said saw during an orbit, next the two chains in the inner lanes of each pair and thereafter the chain associated with the outer lane, and means operably associated with each lane for increasing the speed of the severed log portion to assist in removal of log trim. 